Latch assembly



March 18, 1969 R. E. FOLTZ LATCH ASSEMBLY Filed March 16, 1967 United States Patent 3,433,518 LATCH ASSEMBLY Robert E. Foltz, Sterling, Ill., assignor to Lawrence Brothers, Inc., Sterling, 111., a corporation of Illinois Filed Mar. 16, 1967, Ser. No. 623,681 US. Cl. 292-238 Int. Cl. Ec 3/14 3 Claims ABSTRACT OF THE DISCLOSURE Gate latch assemblies commonly include a strike or latch bar which is fixedly mounted on a gate. The gate is latched or held closed by positioning the latch bar in a slot in a frame and engaging the latch bar with a pawl or trip which is mounted on the frame. The latch bar and gate are then retained by the pawl against movement relative to the frame and a gate post. When the gate is to be opened, the latch pawl is pivoted upwardly to release the latch bar for movement relative to the gate post.

The widespread usage of these prior art gate latch assemblies is eloquent testimony as to their generally satisfactory service. However, difiiculties are encountered in using the prior art gate latch assemblies where the gate tends to sag or droop relative to the gate post. After the gate has begun to sag, the latch bar is out of alignment with its normal position relative to the frame. The prior art latch assemblies are commonly provided with guide or cam surfaces for forcing the latch bar of a sagging gate upwardly into a normal relationship with the frame as the gate is closed. Since the gate is lifted upwardly contemporaneously with the upward movement of the latch bar, the closing of a sagging gate is relatively difficult with prior art latch assemblies. In fact, in cases of severe sagging of a gate, it is sometimes almost impossible to close and latch the gate with prior art latch assemblies.

Therefore, it is an object of this invention to provide a gate latch assembly which overcomes the aforementioned problems and shortcomings of prior art assemblies. Briefly, the invention provides a gate latch assembly which has a latch pawl mounted on a frame including a latch bar receiving slot which is substantially larger than a transverse dimension of an associated latch bar to enable the latch bar of the gate to be readily received in the slot in the event of sagging of the gate.

Another object of this invention is to provide an inexpensive durable latch assembly having relatively few components.

Another object of this invention is to provide a gate latch assembly which enables a latch bar to move vertically relative to a latch pawl and gate post without impeding operation of the latch assembly.

These and other objects and features of the invention will become more apparent upon a consideration of the following detailed description, taken in connection with the accompanying drawings, wherein:

FIG. 1 is a perspective view' of a gate which is retained in a closed position by a gate latch assembly forming a preferred embodiment of the invention;

FIG. 2 is an enlarged perspective view of the gate latch assembly of FIG. 1;

FIG. 3 is an enlarged sectional view, taken along the line 33 of FIG. 2, illustrating a latch frame or bracket and latch pawl or trigger in a position wherein the latch bar and gate are retained against movement by the frame and latch pawl; and

FIG. 4 is a sectional view, similar to FIG. 3 but on a reduced scale, illustrating the latch bar and latch pawl of a sagging gate in an intermediate relationship between a latched and unlatched position.

Referring now to the drawings in greater detail, a gate 10 is pivotally or hingedly mounted on a base or pivot post 12 for movement about an axis of rotation 14 from the closed position illustrated to an open position. A latch assembly 16, forming a preferred embodiment of the invention, is provided for holding or retaining the gate 10 against movement relative to a latch or support post 18. A draw or latch string 22 is connected to the latch assembly 16 and extends through an aperture in the gate post 18 to enable the latch assembly to be operated or released from a far side of the gate 10.

As is perhaps best seen in FIG. 2, the latch assembly 16 includes a latch or strike bar or member 26 which is fixedly mounted on the gate 10 by a suitable connection means such as screws 28. The latch bar extends into a shallow or broad U-shaped slot or recess 32 in a frame or bracket 34 which is fixedly mounted on the gate post 18. A latch or detent pawl or trigger 36 is pivotally connected to the frame 34 by a rivet 38 or other suitable connection means. The latch pawl 36 has a deep or narrow generally U-shaped retaining recess or throat 40 which cooperates with the slot 32 to retain the latch bar against movement outwardly from the latched position shown in FIG. 2.

The latch bar 26 is moved from a released or open position outwardly of the slot 32 and recess 40 to the latched or closed position of FIG. 2 when the gate 10 is pivoted about the vertical axis 14 from an open position to the closed position in which the gate blocks a passageway between the gate post 18 and pivot post 12. As the gate is moved from the open position to the closed position the latch bar 26 is moved into engagement with an arcuate outer cam or drive surface 44- of the pawl 36. Further movement of the gate toward the closed position causes the latch bar 26 to exert an inwardly directed force against the cam surface 44 to pivot the pawl 36 upwardly from the position shown in FIG. 3 to the position shown in FIG. 4. Additional closing movement of the gate 10 causes the latch bar to move past a protuberance or nose 46 of the pawl 36 and into engagement with the slot 32 in the frame 34 and the recess 40 in the pawl 36. As the latch bar 26 is moved past the nose 46, the pawl 36 pivots downwardly from the position shown in FIG. 4 to the position shown in FIG. 3 to hold or retain the latch bar 26 against movement relative to the frame 34.

As can be seen from an inspection of FIG. 3, when the latch bar 26 is in the closed or latched position it is circumscribed by the slot 32 and the recess 40 to hold the latch bar against outward movement relative to the frame 34. If the gate 10 is forced toward the open position with the latch bar positioned as shown in FIG. 3, the latch bar engages the latch pawl and is retained against outward movement. The latch bar 26 is released for outward movement to enable the gate 10 to be opened by pulling the draw string 22 or manually pivoting the pawl 36 by grasping a handle or actuator section or lever 47 of the pawl and pivoting the pawl about the connector pin 38 to the position shown in FIG. 4. Of course, the latch string 22 can be omitted when the gate is to be opened only from the latch side to gain an additional amount of security for a yard or enclosure.

The slot 32 is defined by a pair of parallel horizontally extending side surfaces 50 and 52 which are interconnected by a vertical inner or end surface 54. The slot 32 has a depth, indicated at X in FIG. 3, which is slightly larger than the transverse dimension or diameter of the latch bar 26. The slot 32 has a width, indicated at Y in FIG. 3, which is approximately two and a half times as large as the transverse dimension of the latch bar 26. The relatively large width of the slot 32 enables the latch bar 26 to remain in alignment with the slot even though the gate sags or droops relative to the gate post 18. A sagging of the gate 10 results in a downward displacement of the latch bar 26 from the normal position shown in solid lines in FIG. 3 to the position shown in solid lines in FIG. 4 and indicated at 58 in dashed lines in FIG. 3. It is apparent from an inspection of FIG. 4 that the latch bar 26 of a sagging gate can still actuate the pawl 36 and readily move into the slot 32.

While a slot 32 having a width which is approximately two and a half times as great as the transverse dimension of the latch bar 26 is used in the embodiment of the invention illustrated, it is apparent that the width Y of the slot 32 is determined by the amount of space which is to be allowed for sagging of the gate 10. Thus, it is necessary that the slot 32 have a minimum width Y which is substantially greater than the transverse dimension of the portion of the latch bar 26 which is received in the slot, that is a width Y which is larger than the transverse diameter or dimension of the latch bar 26 by a material or considerable amount corresponding to the expected maximum sagging of the gate. From a practical standpoint, it has been found that slots 32 having a width Y varying from a minimum of from one and one-half (1.5) times the transverse dimension of the latch bar 26 to about five times the transverse dimension of the latch bar 26 are possible without resulting in a latch assembly 16 which is too large and cumbersome for use.

The recess 40 is defined by a pair of spaced apart parallel side surfaces 62 and 64 which are interconnected by an arcuate end surface 66. The protuberance or nose 46 extends inwardly from the side surface 62 to securely hold the latch bar 26 of a sagging gate in the slot 32. The recess 40 has a depth A (see FIG. 4) which is at least as large as the width Y of the slot 32 to enable the position of the latch bar 26 to vary vertically relative to the pawl 36 from the normal position, indicated in solid lines in FIG. 3, to the position indicated in dashed lines at 58 in FIG. 3 when the gate 10 sags. Therefore, the depth of the recess 40 varies by a substantial amount from the transverse dimension or diameter of the portion of the latch bar 26 which is received in the slot 32. In accordance with the aforementioned relative dimension for the slot 32, it has been found that a recess 40 having a depth a from slightly over one and one-half (1.5) times as great as the transverse dimension of the latch bar 40 to approximately four times as great as the transverse dimension of the latch bar 40 is advantageous for use with most gates. The recess 40 has a width b (see FIG. 4) which is slightly larger than an entry way or mouth of the recess or the distance between the protuberance 46 and side surface 64. Of course, the mouth or entry way is in turn slightly larger than the transverse dimension of the latch bar 26, to enable the latch bar to enter the recess 40.

The frame 34 is provided with a pair of opposite spaced apart inwardly converging guide surfaces or jaws 70 and 72 which engage the latch bar 26 to move the latch bar into the slot 32 in much the same manner as is presently done in prior art latch assemblies. However, due to the relatively large width Y of the slot 32 and the relatively large depth a of the recess 40, the latch bar 26 does not engage the guide surface 70 unless an extremely large amount of sag or droop is present in the gate. Since the guide surfaces 70 and 72 seldom, if ever, engage the latch bar 26, it is contemplated that these surfaces may be eliminated in embodiments of the invention other than the preferred embodiment illustrated.

The operation of the latch assembly 16 constructed as illustrated in FIGS. 1 to 4 will be largely apparent from the foregoing description. However, for purposes of affording a more complete understanding of the invention, it is advantageous now to provide a functional description of the mode in which the component parts cooperate. The gate 10 will be retained in a closed position, as shown in FIGS. 1 and 2, by the latch assembly 16 when the latch bar 26 extends into the slot 32 in the bracket 34 and the recess 40 in the pawl 36. A force tending to swing the gate open will result in the latch bar 26 engaging the outer side surface 62 of the recess 40 in the pawl 36. The latch bar 26 will then exert an outward force on the pivot pin 38 and a moment or turning action on the pawl 36 which tends to rotate the pawl about the pivot pin or rivet 38. The outward force will be resisted by the pivot pin 38. The turning action will be resisted by either a stop portion 68 of the frame 34 or by the nose 46 of the pawl, depending upon whether the center of the latch bar 26 is above or below the center of the pivot pin 38. When the draw string 22 is pulled by a person standing on the far side of the gate, as viewed in FIG. 1, or when the release lever section 47 of the pawl is manually grasped to pivot the pawl counterclockwise about the connector pin 38, the latch bar 26 and gate 10 will be released for movement from the closed position of FIG. 1 to an open position. The latch bar will then move out of engagement with the slot 32 and the recess 40, as shown in FIG. 4.

When the gate is swung back to the closed position of FIG. 1, the latch bar 26 will engage the cam surface 44 to pivot the pawl 36 upwardly from the position shown in FIG. 3 to the position shown in FIG. 4, to enable the latch bar to clear the nose portion 46 of the pawl. The pawl 36 will then pivot downwardly, to the position of FIG. 3, to retain the latch bar and gate in the closed position of FIG. 1. The slot 32 and recess 40 will then circumscribe the engaged portion of the latch bar to retain the latch bar against outward movement from the position shown in F1 3.

If during use the gate 10 should sag or move relative to the gate post 18, the latch bar 26 will still be in alignment with the slot 32, since the slot 32 has a width Y which is substantially larger than the transverse dimension of the latch bar 26. Thus, a sagging of the latch bar with the gate from an initial position of installation with the latch bar traversing the upper portion of the slot 32 when the gate is closed, will merely result in a displacement downwardly of the latch bar in the slot 32 and the recess 40. The gate 10 will still be readily closed even though it is sagging, as shown in FIG. 4, since the latch bar does not have to be forced or cammed upwardly to a normal position, as is the case with prior art structures. To obtain this advantageous interrelationship between the latch bar 26 and the frame 34 and pawl 36 it is necessary to make the slot 32 and recess 40 substantially larger than the transverse dimension of the latch bar 26, that is the slot 32 should have a width and the recess 40 a depth which are greater than the transverse dimension of the latch bar 26 by a material amount which corresponds to the expected maximum amount of sag of the gate 10. The cam surface 44 and longitudinal axis of the recess 40 must be related to each other in such a manner as to cause the pawl 36 to ivot upwardly and back again about the pivot pin 38 as the latch bar 26 engages the pawl 36 and moves into the slot 32.

In the illustrated embodiment of the invention, particular constructions of the frame 34 and pawl 36 have been illustrated for use in association with a particular latch bar 26. It is contemplated that the particular structures shown will be changed by those skilled in the art while still using the highly advantageous relationship between the slot 32 in the frame 34 and the latch bar 26, whereby the latch bar will remain in alignment with the slot 32 even though the gate sags. Therefore, while particular embodiments of the invention have been shown, it should be understood, of course, that the invention is not limited thereto since many modifications may be made, and it is contemplated to cover by the appended claims any such modifications as fall within the true spirit and scope of the invention.

What is claimed is:

1. A sag-accommodating gate latch assembly for releasably holding a gate in closed position relative to a gate post; and comprising frame means to be fixedly mounted on the gate post and including an outwardly opening slot, a latch bar to be fixedly mounted on the gate with a portion thereof traversing the slot in said frame means when the gate is closed, the slot in said frame means being of a width substantially vertically longer than the transverse dimension of the latch bar portion to be received therein by a distance to effectively accommodate substantial gate sagging from an initial position of installation of the latch bar and frame means on the gate and gate post, respectively, with the latch bar portion initially traversing the upper portion of the slot when the gate is closed, and a pawl pivotally connected to the frame means and including an outwardly facing cam surface to be engaged by the latch bar portion for pivoting the pawl upwardly when the gate is moved to closed position, said pawl including a recess opening at the bottom thereof to receive the latch bar portion as the pawl is pivoted upwardly upon movement of the latch bar portion into the slot in said frame means, the recess in the pawl being defined along one side by a wall surface thereof traversing the slot in the frame means when the gate is closed to trap the latch bar portion in the slot and in the initial position thereof traversing the upper portion of the slot as well as in lower positions thereof traversing lower portions of the slot resulting from sagging of the gate relative to the gate post.

2. An assembly as set forth in claim 1 wherein: the width of said slot in said frame means and the depth of the recess in said pawl are at least one and one-half times as large as the transverse dimension of the portion of said latch bar which is received into said slot, whereby the portion of the latch bar which is received into said slot is engaged by said pawl and said frame means to retain said latch bar against movement relative to said frame means while enabling the gate to sag relative to both said frame means and said pawl.

3. An assembly as set forth in claim 1 wherein the slot in said frame means has a width between 1.5 to 5 times the transverse dimension of said latch bar and said recess in said pawl has a depth between 1.5 to 4 times the transverse dimension of said latch bar.

References Cited UNITED STATES PATENTS 844,907 2/1907 Aikin 292-136 974,566 11/1910 Giles 292-136 3,266,831 '8/ 1966 Banse 292-133 627,750 6/ 1899 Happy 292-99 FOREIGN PATENTS 122,131 9/ 1946 Australia.

RICHARD E. MOORE, Primary Examiner.

US. Cl. X.R. 292-235 

